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21.
Administration of 10 micrograms of substance P intrathecally to the spinal T9 level of the adult rat, anaesthetized with urethane, provoked an increase in free catecholamines in plasma taken from the inferior vena cava. Adrenaline levels at 1 min after administration were 154.8 +/- 10.8% (mean +/- SE; n = 11) of preadministration levels and noradrenaline levels were 153.5 +/- 11.8% of preadministration levels. Differences between the values of free catecholamines in animals given substance P vs those given vehicle only were statistically significant at 1 and 10 min postinjection, but not at 30 min. Administration of a substance P analogue with central antagonistic properties 15 min before substance P was given prevented expression of the effects of substance P. These results suggest that substance P may be an excitatory chemical mediator of synaptic transmission in spinal pathways controlling adrenal medullary output. Thus dysfunction of substance P mechanisms may underlie some animal models of hypertension and may be involved in some cases of essential hypertension in man as well as in autonomic dysfunction associated with some neurological entities. 相似文献
22.
Human leukocyte antigen matching and fetal loss: results of a 10 year prospective study 总被引:6,自引:0,他引:6
Ober C; Hyslop T; Elias S; Weitkamp LR; Hauck WW 《Human reproduction (Oxford, England)》1998,13(1):33-38
The role that maternal and fetal human leukocyte antigen (HLA) genes play
in pregnancy is unknown, but it has been suggested that fetuses whose HLA
alleles do not differ from maternal alleles (i.e. histocompatible fetuses)
are more likely to be aborted than fetuses with HLA alleles that differ
from maternal alleles (i.e. histoincompatible fetuses). To elucidate the
role of HLA compatibility in pregnancy, we tested the hypothesis that
couples who match for HLA alleles or haplotypes would have reduced
fertility because only these couples could produce histocompatible fetuses.
We conducted a 10 year prospective study of HLA matching and pregnancy
outcome in 111 Hutterite couples, providing information on 251 pregnancies.
A logistic regression analysis was performed to determine the effects of
HLA matching at HLA regions and loci on pregnancy outcome (fetal loss
versus delivery). Significantly increased fetal loss rates were observed
among couples matching for the entire 16-locus haplotype (P = 0.002). Among
the individual loci, loss rates were increased among couples matching for
HLA-B (P = 0.019), HLA-C (P = 0.033) and the complement component, C4 (P =
0.043). We interpret these results as evidence that matching for the entire
16-locus haplotype and/or alleles at an HLA-B-linked locus confers
significant risk for fetal loss.
相似文献
23.
Schover LR; Thomas AJ; Falcone T; Attaran M; Goldberg J 《Human reproduction (Oxford, England)》1998,13(4):862-866
Many couples undergoing in-vitro fertilization (IVF) are at a higher risk
of having a child with a genetic abnormality. In a sample of 55 consecutive
couples starting IVF, only 33% had no genetic risk factor. The most common
genetic risks were advanced maternal age and possible abnormalities
associated with severe male infertility. Despite education on these risks,
71% of couples had no interest in receiving formal genetic counselling.
Only 14% of couples at risk would consider using a gamete donor to avoid
transmitting a genetic disorder to a child. The triple test to screen for
fetal abnormalities was acceptable to 82% of couples, but only 47% planned
to have amniocentesis or chorionic villi sampling. Couples were
significantly more likely to opt for prenatal testing if they would
consider terminating a pregnancy should the fetus have a severe genetic
abnormality (P < 0.01). Roman Catholic couples tended to have more
conservative attitudes about pregnancy termination. Socio-economic status
and whether the infertility factor was male or female were not predictors
of a couple's attitudes.
相似文献
24.
Tenenhouse HS Gauthier C Martel J Hoenderop JG Hartog A Meyer MH Meyer RA Bindels RJ 《Pflügers Archiv : European journal of physiology》2002,444(5):670-676
Mice homozygous for the disrupted type-II Na/P(i) cotransporter gene ( Npt2(-/-)) exhibit hypophosphataemia, increased serum concentration of 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) and calcium (Ca) and elevated urinary Ca excretion. To determine whether the hypercalcaemia and hypercalciuria are secondary to 1,25-(OH)(2)D-stimulated intestinal Ca absorption, we examined the effect of Npt2 gene disruption on serum Ca and urinary Ca excretion after an overnight fast, and on duodenal Ca absorption. We also compared the duodenal expression of the epithelial Ca channels, ECaC1 and ECaC2, and calbindinD(9K) mRNAs, relative to that of beta-actin mRNA, in Npt2(+/+) and Npt2(-/-) mice. Both serum Ca and urine Ca/creatinine were significantly decreased in Npt2(-/-) mice after an overnight fast and were no longer different from that in wild-type mice. Absorption of (45)Ca from isolated duodenal segments in vivo and (45)Ca appearing in the plasma were significantly increased in Npt2(-/-) compared with Npt2(+/+) mice. In addition, the duodenal abundance of ECaC1, ECaC2 and calbindinD(9K) mRNAs was significantly elevated in mutant mice relative to that in wild-type mice. In contrast, both duodenal Ca absorption and ECaC1 and ECaC2 mRNA abundance were lower in mice with X-linked hypophosphataemia ( Hyp) than in normal littermates. In summary, we provide evidence for increased duodenal Ca absorption in Npt2(-/-) mice and suggest a role for ECaC1, ECaC2 and calbindinD(9K) in mediating this response. 相似文献
25.
Autosome and Sex Chromosome Diversity Among the African Pygmy Mice, Subgenus Nannomys (Murinae; Mus)
Frédéric Veyrunes Josette Catalan Bruno Sicard Terence J. Robinson Jean-Marc Duplantier Laurent Granjon Gauthier Dobigny Janice Britton-Davidian 《Chromosome research》2004,12(4):369-382
The African pygmy mice, subgenus Nannomys, constitute the most speciose lineage of the genus Mus with 19 recognized species. Although morphologically very similar, they exhibit considerable chromosomal diversity which is here confirmed and extended by the G-banding analysis of 65 mice from West and South Africa. On the basis of their karyotype and distribution area, the specimens were assigned to at least five species. Extensive differentiation both within and between species was observed that involved almost exclusively Robertsonian translocations, 23 of which are newly described. Two of the rearrangements were sex chromosome-autosome translocations, associated in some cases with partial deletions of the X or Y chromosomes. Several authors have predicted that the highly deleterious effect of this rearrangement would be reduced if the sex and autosomal segments were insulated by a block of centromeric heterochromatin. The C-banding analyses performed showed that among the species carrying X-autosome translocations, one followed the expected pattern, while the other did not. In this case, functional isolation of the sex and autosome compartments must involve other repetitive sequences or genomic traits that require further molecular characterization. Such studies will provide insight into the causes and consequences of the high diversity of sex chromosome rearrangements in this subgenus. 相似文献
26.
27.
28.
Ferlicot S Quillard J Chardot C Caillou B Oberlin O Gauthier F Fabre M 《Annales de pathologie》1999,19(6):521-524
Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of children. Tumors arising in the extrahepatic biliary tree are extremely rare (less than 1% of cases). In this location, most are RMS of the botryoid type. We report a case of a 10-year-old child with embryonal RMS arising in the mesenchyma of the hepatic pedicle. Most tumor cells were large, round with abundant eosinophilic cytoplasm. A few cells were small round or spindle-shaped. Tumor cells showed positive immunostaining for muscle markers: desmin and sarcomeric actin. Electron microscopy revealed 2 types of cells: some were undifferentiated and others showed striated muscle differentiation features. 相似文献
29.
30.
Boman F Farré I Farine MO Leroy JL Gauthier A Querleu D Vacher-Lavenu MC 《Clinical and experimental pathology》1999,47(2):81-87
The study evaluated the feasibility of a thinlayer technique on a routine basis for cervical smears and compared 473 ThinPrep preparations to the matched conventional Papsmears. The interpretation was double-blind and performed according to the Bethesda system. A consensus was established in discordant cases. The technique was easily mastered by gynecologists and technicians. Main advantages of the thinlayer technique were: a low number (1%) of unsatisfactory samples; a constant quality; homogeneity of cell distribution; the disappearance of problems of interpretation due to fixation or smear artifacts, red cells, polymorphs; a more precise interpretation, a firmer diagnosis; less visual fatigue; a shorter time of interpretation; the possibility of preparing more slides and performing special techniques on the same specimen. Main disadvantages were a higher cost and a necessary period of learning for cytologists. 相似文献